According to court records, Selis was married, he had two children and one stepson. Selis worked as a mechanic at Mossy Ford in Mission Bay.

Court records also showed he had financial problems and filed for bankruptcy twice. First in 2009, with his former wife, he claimed he owed more than $400,000. Selis also filed a second time in 2015, claiming he owed more than $100,000.

Selis' friends told CBS News 8 they were stunned to learn about Sunday's events. While friends did not know him as someone who was violent, his attorney, however, said based on recent conversations, Selis was very depressed.

He had previously tried opening his own private business, but Steven Houbeck said over the years the debt from the failed shop continued to rack up.

"A big chunk of the debt was the franchise tax board which was very aggressive against him. They were going after his bank accounts, levying paychecks," said Houbeck.

Tom Tulloch said he grew up with Selis in Allied Gardens. He ran into him six months ago. "we were talking about our families - how happy he was. I would never imagine Pete doing such a thing. That's just not who Pete was," said Tulloch.

Salis had recently broken-up with his girlfriend. During the rampage, he called her on his cellphone so she could listen as he carried out the shooting.

The San Diego Police Department received multiple calls just after 6 p.m. regarding an active shooter in the 9000 block of Judicial Drive. He was described as a white male who was armed. Selis, 49, reportedly lived at the apartment complex where the shooting took place.

When police officers arrived on scene they were directed to the pool area where they located the suspect who then pointed and fired his weapon at the officers, according to Police Chief Zimmerman.

Three officers opened fire on the suspect, he went down and was confirmed to be dead.

His body was removed from the complex Monday just before 5:30 a.m.

CBS News 8 has learned that Peter Selis had several siblings. He was also the son of a prominent San Diego dentist, Dr. Robert Selis, who passed away in 2009.

Selis graduated from Patrick Henry High School in 1986. The quote from his yearbook said, "Faithful to some, loyal to none. I love you mom and dad."

According to court documents, Selis had no criminal history - just a traffic ticket for making an illegal left hand turn.

The Selis family released the following statement on Monday:

"Our family feels the unbearable pain caused by Pete's senseless acts. We cannot understand what would have caused Pete to do this. Words cannot express our profound grief and sorrow for all the victims and their families. On behalf of our family, we are so sorry that this happened. We ask that you please respect our privacy. We will miss our beloved Pete forever."